线材修磨的磨削压力与砂带速度

本文根据砂带与线材间的接触状态,讨论了砂带修磨线材机理的有关问题,导出了磨削压力、砂带速度与金属去除率之间的关系.试验结果表明;磨削压力的变化对磨削过程具有极为重要的影响,增大磨削压力可大大地提高磨削生产率,降低比磨削能.     

Helium isotopic compositions in fluid inclusions of the Gangxi fault belt in the Huanghua Depression, Bohai Bay Basin

Helium is a trace constituent in natural gases and is the lightest element of all rare gases. Formed during natural nuclear processes, helium is chemically stable. Due to its strong diffusibility and permeability, helium can be used as a very sensitive tracer. Helium has two natural stable isotopes, 3He and 4He. 3He originates from the universal nebulae when the earth was formed, and 4He mainly originates from the radioactive disintegration of elements in the crust, such as U and Th [1]. In…     

提高大面积混凝土墙身外现质量的措施

根据混凝土施工经验,加强对混凝土施工各道工序的把关.针对混凝土墙身表面出现的缺陷,提出施工处理方法和注意事项,使混凝土墙身外观质量有很大提高.     

热带太平洋和印度洋海温对中国雨带类型的影响

 根据1950~1999年的海温距平和中国夏季(6~8月)雨带分布类型资料,分析了各雨型与前期及同期热带太平洋和印度洋(21°S~21°N,29°E~81°W)海温异常的相关关系.分析表明,不同雨带类型和所对应同期及前期太平洋和印度洋海温有很好的相关关系.     

浅谈长江上游经济带的地位和作用

在经济全球化的条件下，区域经济一体化是全面推进工业化与城市化进程的必然选择．谁能在区域经济一体化的发展进程中占有先机，谁就能在经济全球化的竞争中获胜．在此背景下，准确把握长江上游经济带的地位和作用显得尤为重要．本文通过对长江上游经济带特征的分析，从全国生产力布局、西部大开发战略和长江流域经济开发三个方面对长江上游经济带的地位和作用进行了论述．     

浅谈长江上游经济带的地位和作用

在经济全球化的条件下,区域经济一体化是全面推进工业化与城市化进程的必然选择.谁能在区域经济一体化的发展进程中占有先机,谁就能在经济全球化的竞争中获胜.在此背景下,准确把握长江上游经济带的地位和作用显得尤为重要.本文通过对长江上游经济带特征的分析,从全国生产力布局、西部大开发战略和长江流域经济开发三个方面对长江上游经济带的地位和作用进行了论述.     

Geochemical characteristics and tectonic implications of HP-UHP eclogites and blueschists in southwestern Tianshan, China

Four rock assemblages in correspondence with two different tectonic settings have been recognized in the NEE-SWW extending HP-UHP metamorphic belt in southwestern Tianshan, northwest China. Eclogite assemblage EC1 is geochemically akin to alkaline within-plate oceanic island basalt (OIB). EC2 shows affinity to enriched mid-oceanic ridge basalt (EMORB). Rare earth element (REE) and other immobile trace element characteristics of blueschist assemblage BS1 resemble those of normal mid-oceanic ridge basalt (NMORB). These three assemblages are likely formed on a seamount setting, and the prevalent presence of carbonate minerals and omphacite quartzite stripes/gobbets suggests ancient pelagic sediments including marls are probably developed upon the basaltic seamount. Whereas the geochemical characteristics of BS2 assemblage are of volcanic arc basalt-type. The seamount with the pelagic sediments on it is brought into the subduction zone, and volcanic arc basalts formed on the active continental margin and trench sediments are eroded and enwrapped in the subducting mass, they are altogether subjected to high to ultrahigh pressure metamorphism and subsequent exhumation towards surface. The HP-UHP metamorphic belt is thus interpreted as a subduction-accretionary complex formed by tectonic juxtaposition and imbrication of seamount, seafloor, trench and volcanic arc sequences during oceanic crust subduction.     

Abnormal high pressure in Kuqa foreland thrust belt of Tarim basin: Origin and impacts on hydrocarbon accumulation

Following analyses of the abnormal high pressure distribution characteristics, based on the geological characteristics, tectonic stress field and physical simulation, we investigated the formation mechanisms of abnormal high pressure and its impacts on hydrocarbon accumulation in the Kuqa foreland thrust belt. The abnormal high pressure appears at the bottom of the Paleogene and obviously exists in the Triassic and Jurassic. However, the pressure coefficient in the Triassic and Jurassic is lower than that in the Cretaceous and at the bottom of the Paleogene. Horizontally, the abnormal high pressure distribution is characterized by E-W orientation zoning. The maximum pressure coefficient lies in the Kelasu-Dongqiu-Dina tectonic zones in the center of the Kuqa foreland thrust belt and decreases away from the tectonic zones. The formation of abnormal high pressure was mainly related with the intense tectonic compression in the Early Pleistocene time, and tectonic uplifting, undercompaction and hydrocarbon generation were secondary factors contributing to abnormal high pressure. Under the rapid and intense tectonic compression in the Early Pleistocene, the rock framework firstly undertook 1/4 of the compression stress and the other was borne by the pore fluids. Due to the presence of great seal of gypsum-salt or gypsum-mudstone beds in the Paleogene, the pressure of pore fluids increased rapidly and led to the abnormal high pressure in the Kuqa foreland thrust belt. The abnormal high pressure has important impacts on hydrocarbon accumulation. It is one of the necessary conditions for formation of large oil and gas fields in the Kuqa foreland thrust belt.     

龙泉矿井大巷带式输送机驱动方式的选择

分析了带式输送机多种驱动方式的优缺点,并根据实际情况选择了驱动装置。     

环城市带休闲旅游产品开发研究--以重庆市巴南区为例

环城市带是城镇居民休闲旅游的重要目的地，对其开发具有重要的意义，通过分析环城市带开发休闲旅游的条件，由此提出环城市带休闲旅游产品开发的五基本模式，并以重庆市巴南区为例进行实例分析，最后指出了环城市带休闲旅游开发应注意的问题。